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Turboivo · Joined: 09 Mar 2006 Posts: 683 Location: Bulgaria

I've seen at least 1-2 China manufacturers of these coils on the web. The offered price (wholesale?) was 11-13 usd.

Pantera EFI · Joined: 12 Feb 2005 Posts: 1283 Location: So. California

This first remark is for Ivo : MOST ignition coils ARE made in China.
The sad fact is USA manufactures, some, have inferior products.
The BEST coils are designed in the USA.
The MAIN reason is that China has the "rare earth" magnet agenda.
China believes THEY should be the planet provider of products that use Rare Earth magnets, thus costs are kept in line.
Reality : We all know that there are GOOD/BAD tuners and GOOD/BAD manufacturers, thus product reputation exists.

Three years ago we were commissioned to provide an aftermarket GM Gen-IV coil. The requirement was for the same form, footprint, connections (a-bit).
The FIRST item I changed was the dwell/stall (coil saver/engine destroyer) circuit.
MY thought is that the EMS should be the "brains" of the running engine NOT a coil.
Next the driver current capacity was tripled (36 AMP-64 AMP, 500 mJ, IGBT fitted) based on internal temperature.
Coil frame, turns ratio, magnet placement were also revised.

First testing a year ago stated an improvement, reduction, in Charge Time, reduced by 1 ms.
The coil, when tested in my CO-2 chamber found an internal conductive path when dwell was above 6 ms. (400 psi)
This test greatly exceeded OEM specification.

Second design, tested four months ago, found this problem solved at the higher than OEM specified testing method.

This IGN-GM4 coil is in a production (10,000) unit build.
This coil is currently running on race cars required for certification.
This coil is being tested at OEM heat cycle/accelerated life methods.

Lance
,

skylinegtrhr · Joined: 14 Oct 2009 Posts: 33 Location: Croatia

Thanks Lance for detail explanations,

can You give us some price as I can't find any info on Yours site?
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http://www.nistune.nissan-club.hr/

Pantera EFI · Joined: 12 Feb 2005 Posts: 1283 Location: So. California

Your interest is appreciated, the task of production is not completed.
PM for a projected price and picture.

Lance Nist, BTW your site states NISTune ???

Turboivo · Joined: 09 Mar 2006 Posts: 683 Location: Bulgaria

So finally are those coils indeed so good as rumours said when/if dwell is kept under 5 ms?
Thanks!

TurboNova · Posted: Thu Jul 26, 2012 8:31 am Post subject:

I wont use them, there are others that are way better. Too many issues with over dwell or over dwell on cranking ect..

Like I said the dwell curve isn't a linear line with voltage like most coils are.
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Brian Macy
EFI University Instructor
Horsepower Connection
www.horsepowerconnection.com

RootesRacer · Joined: 04 Apr 2005 Posts: 464 Location: Arvada, Colorado

TurboNova · Posted: Thu Jul 26, 2012 10:42 am Post subject:

RootesRacer · Joined: 04 Apr 2005 Posts: 464 Location: Arvada, Colorado

TurboNova · Posted: Sat Jul 28, 2012 10:11 pm Post subject:

Your not getting it, when tested the spark energy did not always go up as dewell time did. The spark energy was all over the place. You would expect the coil to put out more charge as dwell time is increased but it did not always. The charge time vs spark output is not linear and not just above 5ms.
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Brian Macy
EFI University Instructor
Horsepower Connection
www.horsepowerconnection.com

Turboivo · Joined: 09 Mar 2006 Posts: 683 Location: Bulgaria

Here I found some good info on these round truck coils:

http://www.yellowbullet.com/forum/showthread.php?t=337602

TurboNova · Posted: Tue Apr 30, 2013 12:51 pm Post subject:

So much bad info on YB. These round truck coils are junk.. the dewll curve isnt a linear curve like everyone believes. They do have issues and I wouldnt use them in any performance application. The more square( LS2/and later truck coils)without heat sync work great. There really isn't any more to say or research, the round coils are junk.
_________________
Brian Macy
EFI University Instructor
Horsepower Connection
www.horsepowerconnection.com

joe90 · Joined: 19 Mar 2013 Posts: 27

There's 2 different ways to stop coils from getting saturated.
One is to control the dwell time.
The other is to internally limit the current via a resistor or by other means.
Not all factory computers control the factory coils(prevent saturation) with timing control.
If a coil has an inbuilt igniter with a heatsink, then it's probably limiting the current. It might even go one step further and automatically switch off the coil current if it doesn't get a turn off signal after a certain time period? that's to stop it getting too hot. Maybe they're actually faulty?
Once a coil is saturated, it's effectively "full" and turning up the current doesn't make more volts at the spark

The best way to determine what's going on is on a bench with a signal generator and an oscilloscope.

It's a bit silly saying that something is rubbish if you don't know what's going on.

BTW capacitors charge as do batteries.
Coils "flux". Coils don't charge. You'd get an instant fail for that.
That's what you learn at school and at a real university.

I see from one of the links provided someone was trying to make coils with permanent magnets in them ? I guess that never eventuated due to hysteresis.

PanteraTurbo · Joined: 28 Jul 2007 Posts: 128 Location: Victoria, BC

Its wild that I should find this thread now. I have been beating my head against a Nissan CA18DET running four truck coils with heatsinks. Its using a 36-1 crank wheel and a stock CAS for home signal. At 5.5ms dwell we were seeing timing scatter by as much as 15 degrees and high rpm by even more. After turning the dwell down to 3ms ALL scatter went away. It doesnt seem to matter if its anywhere in between those numbers it doesnt stop till 3ms and at that point its like someone flipped a switch. I should also note that I am running eight of these on my car at 5.5ms with NO issues.
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Blaine Carmena
blaine@5252motorsports.com